Congenital Heart Defects Flashcards
What is the haemodynamic effect of a L-R shunt?
In terms of oxygenation, this is not a concern here. However there is increased blood flow around the pulmonary circulation which can lead to pulmonary hypertension and damage to the pulmonary vessels.
What is the problem with a R-L shunt?
This means that deoxygenated blood bypasses the lungs and enters the systemic circulation. This causes cyanosis.
What type of defects are aortic stenosis, pulmonary stenosis, coarctation of aorta and mitral stenosis all examples of?
Acyanotic defects. The blood is still sufficiently oxygenated.
Give some examples of cyanosis heart defects.
Tetralogy of Fallot, R to L shunts, transposition of great vessels, univentricular heart.
With which organ do we associate the cause of cyanosis to lie?
Heart. The lungs are very complex organs and so if oxygenation is insufficient then they can divert blood elsewhere.
What problems can be associated with Atrial Septal Defect?
This is where there is a hole in the interatrial wall. Blood is shunted L to R causing increased blood flow through R side of the heart. Pulmonary hypertension and R side heart failure can occur.
Where in the interventricular wall does ventricular septal defect most commonly occur?
It most commonly occurs in the membranous portion, however it can occur at any point in the septum.
What effect on the left ventricle does ventricular septal defect have?
This causes a L to R shunt meaning there is increased blood flow into the pulmonary circulation. This leads to LV overload due to the excess venous drainage.
What is the effect of Ventricular septal defect on the body?
As it is a L to R shunt there is a lower volume of blood pumped to the body so the heart has to pump harder to ensure that blood supply is sufficient.
What is the name for the condition where there is obstruction of blood flow into aorta during systole due to narrowing of the aortic valve?
Aortic stenosis
What is coarctation of aorta and what does it cause?
This is a narrowing of the aorta which commonly occurs after the left subclavian vein. This leads to high BP in the upper limbs and low BP in the lower limbs.
What is unusual about the congenital heart defect: tetralogy of Fallot?
The interplay of the four defects makes it compatible with life.
What defects comprise tetralogy of Fallot?
Pulmonary stenosis, VSD, right ventricular hypertrophy and overriding aorta.
What is the significance of pulmonary stenosis being a defect in tetralogy of Fallot?
It prevents high blood flow through the pulmonary circulation.
What is tricuspid atresia? What is required for there to be blood flow to the lungs?
This is where there is no blood flow from RA to RV. There is an entire R to L shunt of the venous return. For blood to get to lungs,beds a patent ductus arteriosus or a VSD.
